Implant inserter

ABSTRACT

An apparatus for inserting an implant between vertebrae includes a body having a through bore, a central shaft movable within the through bore, the central shaft having a proximal end and a distal end. The apparatus includes a pair of distractor arms having proximal portions and distal portions, the proximal portions pivotally coupled to the body and distal portions for engagement between the vertebrae. Tracking slots are formed in and extend through surfaces of and along a longitudinal axes of the distractor arms and an attachment tip is operably connected to the central shaft, the attachment tip is configured to grip the implant. The apparatus includes a single guide member projecting outward from the attachment tip and the attachment tip is removably connectable to the central shaft in multiple configurations.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 13/408,188 filed on Feb. 29, 2012, which is incorporated in itsentirety herein.

FIELD OF THE INVENTION

The present disclosure relates generally to devices used to installimplants between vertebrae.

BACKGROUND OF THE INVENTION

Portions of the spine are linked together in part by intervertebraldiscs, which are discs that lie between vertebrae. Damage to these discscan result from sports injuries, accidents, infections, wear and tearover time and other causes. One type of treatment for this damage,involves removal of the damaged disc between vertebrae and insertion ofan implant into the disc space. The insertion of the implant canmaintain the natural separation between vertebrae.

Spinal inserter instruments can be used to install implants betweenvertebrae. These devices are usually operated manually and can includeelements such as distractor arms to spread apart the disc space and ashaft with a holder used to grip the implant and move it into position.After the implant is inserted, the instrument can be removed.

SUMMARY OF THE INVENTION

An apparatus for inserting an implant between vertebrae includes a bodyhaving a through bore, a central shaft movable within the through bore,the central shaft having a proximal end and a distal end. The apparatusincludes a pair of distractor arms having proximal portions and distalportions, the proximal portions pivotally coupled to the body and distalportions for engagement between the vertebrae. Tracking slots are formedin and extend through surfaces of and along a longitudinal axes of thedistractor arms and an attachment tip is operably connected to thecentral shaft, the attachment tip is configured to grip the implant. Theapparatus includes a single guide member projecting outward from theattachment tip and the attachment tip is removably connectable to thecentral shaft in multiple configurations.

BRIEF DESCRIPTION OF THE DRAWINGS

The various embodiments disclosed herein are illustrated by way ofexample and not by way of limitation in the figures of the accompanyingdrawings, in which like reference numerals refer to similar elements.

FIG. 1 is a perspective view of an example embodiment of an implantinserter;

FIG. 2 is a top view of the implant inserter shown in FIG. 1;

FIG. 3 is a sectional view taken on line A-A of FIG. 2;

FIG. 4 is a perspective view of an example embodiment of an attachmenttip that can be used with the implant inserter of FIG. 1;

FIG. 5 is a side view of the attachment tip shown in FIG. 4;

FIG. 6 is a top sectional view taken on line A-A of FIG. 5 with anexample embodiment of an implant;

FIG. 7 is a perspective view of the attachment tip of FIG. 4 with theexample implant of FIG. 6;

FIG. 8 is a perspective view of an example embodiment of a prongedattachment tip that can be used with the implant inserter of FIG. 1;

FIG. 9 is a side view of the attachment tip shown in FIG. 8;

FIG. 10 is a top sectional view taken on line A-A of FIG. 9; and

FIG. 11 is a perspective view of the attachment tip of FIG. 8 with anexample embodiment of an implant.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1-3, illustrate an embodiment of an implant inserter 10 forinserting an implant between vertebrae (not shown). The implant inserter10 can include a body 12 that has a bore 14 and a central shaft 16 thatis movable through the bore 14. The central shaft 16 has a proximal end(closer to the user) and a distal end (closer to the surgical site). Apair of distractor arms 18 have proximal portions pivotally coupled tothe body 12 and distal portions for engagement between the vertebrae.The central shaft 16 includes a tip adapter 20 located at its distalend.

Referring to FIGS. 1, 4, and 5, in one embodiment, an attachment tip 40is operably connected to the tip adapter 20 and central shaft 16. Theattachment tip 40 is configured to grip the implant 4 in a manner thatthe implant 4 can be easily inserted between the vertebrae. Referring toFIGS. 1, 3, and 4, the attachment tip 40 is designed to be attached inmultiple configurations relative to the general plane of operation ofthe implant inserter 10. The attachment tip in part ensures properguidance, alignment and insertion of the implant.

Referring to FIGS. 1-3, in an embodiment, the body 12 includes a firsttubular portion 22 and a second tubular portion 24. The first tubularportion 22 may be centrally located so that a user can optionally holdit for support and guidance during operation of the implant inserter 10.The first tubular portion 22 includes recesses 26 formed therein toprovide texture for the user's grip. In an example embodiment, the firsttubular portion 22 has internal threads (not shown) formed at its distalend and configured to accept external threads that can be formed on thecentral shaft 16. The shaft includes a handle 11 for ease of use andoperation.

The first tubular portion 22 has a clutch mechanism or actuator 23, thatcan have an off position and an engaged position. In an exampleembodiment, when the actuator 23 is in the off position, the centralshaft slides freely and can be driven longitudinally straight forward ina distal direction. In an alternative approach the actuator 23 can bemoved to the engaged position. When the actuator 23 is in the engagedposition, the central shaft 16 does not slide freely, however it can bemoved forward through rotation of the handle.

When the central shaft 16 is moved forward in the engaged position withrotational drive action, the external threads and internal threads willengage. In an embodiment, the actuator 23 is a push button. It can alsobe a cam mechanism. Any suitable clutch mechanism can be used for theactuator 23. In an alternative embodiment, the actuator 23 may include amode that allows for the user to use a ratchet type action to drive thecentral shaft 16 forward. In an embodiment, a dial 13 positioned justdistal to the handle 11 and can be rotated to move the tip adapter toengage and disengage the implant. The dial 11 provides precisioncontrol.

Referring again to FIGS. 1-3, in one embodiment, the body can have asecond tubular portion 24 that is tapered and extends from a distal endof the body 12. The second tubular 24 portion provides an additionalguiding support for the central shaft 16. Windows 28 are included in thesecond tubular portion 24 so that a user can track the progress of thecentral shaft 16.

In an embodiment, the first tubular portion 22 and second tubularportion 24 are generally circular in cross section. However any crosssectional shape could be used, for example but not limited torectangular, elliptical or square. The first tubular portion 22 and thesecond tubular portion 24 can be joined using an interference fit,adhesive or a threaded connection. Alternatively, the first tubularportion 22 and second tubular portion 24 can be monolithically molded asone piece. In an example embodiment, the first tubular portion andsecond tubular portion may be comprised of aluminum, steel, plastic,and/or silicone. However, any material suitable for surgicalapplications may be used, such as but not limited to plastic, compositeand metal.

Referring to FIGS. 1-3 the central shaft 16 has a proximal end and adistal end. In an example embodiment, the proximal end of the centralshaft includes external threads 30 sized and configured to join withinternal threads formed on the first tubular portion 22 of the body 12.The remaining distal portion of the central shaft 16 can be straightwithout threads or can include ball, triangular, trapezoidal, and/orsquare screws. In an example embodiment, the central shaft 16 iscircular in cross section. In alternate embodiments, the central shaft16 can be any cross sectional shape such as but not limited toelliptical, square or rectangular. The central shaft may be made ofsteel. However, any material suitable for surgical applications may beused, such as but not limited to plastic, composite and metal.

In an embodiment, a tip adapter 20 is formed at the distal end of thecentral shaft 16. The tip adapter 20 and the distal end of the centralshaft are sized and shaped to interface with and retain the attachmenttip 40.

Referring to FIG. 1, in an example embodiment, a pair of distractor arms18 are pivotally coupled to the second tubular portion 24 of the body12. The distractor arms 18 are attachable to a coupling adapter 32including two slots 34. The coupling adapter 32 is releasably attachedto the second tubular portion 24. In another embodiment, the secondtubular portion 24 and the coupling adapter 34 are formed as onemonolithic piece.

Coupling pins 36 can be placed through slots 34 to join proximal ends ofthe distractor arms 18 to the coupling adapter 32. This configurationpermits the distractor arms 18 to freely pivot. Also, distractor arms 18can easily be interchanged for different sizes depending upon theparticular requirements of the user, procedure, and surgicalapplication. In addition to providing interchangeability, thisconfiguration allows for distractor arms 18 to be easily removed forcleaning and sterilization.

In an example embodiment, at least one of the distractor arms 18includes a tracking slot 38 extending along its length from the proximalto distal ends. Stop members 39 are formed at the distal ends of thedistractor arms 18 and are shaped and configured to abut againstvertebrae to provide stability during the operation of the inserterinstrument. In an example embodiment, the stop members 39 include aforward rectangular endface designed to abut the vertebrae. In anotherembodiment, the stop members 39 can be adjustable for varying depths.

Referring to FIGS. 2-4, the attachment tip 40 can be operably connectedto the central shaft 16. The proximal end of the attachment tip 40includes a detent groove 41 and also has an internally disposed centralbore 42. The detent groove 41 is designed to interface with acorresponding rib (not shown) on the central shaft 16. In oneembodiment, the tip adapter 20 and central shaft 16 are attached bythreading the tip adapter 20 into the central bore 42 and sliding therib on the second tubular portion 24 into the detent groove 41 toprovide a secure connection between the central shaft 16 and theattachment tip 40. As tip adapter 20 is slid, the attachment tip 40slides onto the central shaft 16 through detent groove 41, causing theslider to capture the attachment tip 40.

Referring to FIGS. 4-7, a distal face of the attachment tip 40 includesfastening features configured to grip and retain an implant. In anexample embodiment, the fastening features include a screw thread tip 44and a rib 46. Referring to FIG. 5, implant 4 may include a tapped recess48 that is sized and shaped to cooperate with threads on the screwthread tip 44. In an example embodiment, implant 4 can also includerecesses 49 adapted to cooperate with ribs 46 to provide an interferencefit between attachment tip 40 and implant 4.

Referring to FIGS. 1, 3, and 4-7, in an embodiment, a guide member orfin 50 projects in a generally orthogonal outward direction from theattachment tip 40. Fin 50 is sized, shaped and configured to slidewithin tracking slot 38 of guide member 18 to help guide the attachmenttip 40 towards moving the implant 4 into a proper position between thevertebrae. The guide member or fin 50 may also be configured to slide onthe outside of the guide member 18.

In one embodiment, the fin 50 is monolithically formed as part of theattachment tip 40. In other embodiments, the fin 50 is a separate piecethat can be secured to the attachment tip 40 in a number of waysincluding but not limited to using a rib and recess, rail and groove, afastener or adhesive. In an example embodiment, the fin 50 is triangularshaped in cross section or tapered. However the fin 50 may have any sizeor shape suitable to cooperate with the tracking slot.

Referring to FIGS. 1 and 8-11, an example alternative embodiment of apronged attachment tip 52 is shown. The pronged attachment tip 52 can beoperably connected to the central shaft 16. The proximal end of thepronged attachment tip 52 includes a detent groove 51 and also has aninternally disposed central bore 52. The detent groove 51 interfaceswith a corresponding rib (not shown) on the central shaft 16.

A distal surface of the pronged attachment tip 52 has a base portion 54with fastening features configured to releasably grip an implant 6. Inan example embodiment, the fastening features include a pair of prongs56 pivotally attached to the base portion 54. A support shaft 58 extendsdistally outward between the prongs 56. Prongs 56 have distal end faces55 including inwardly facing ribs 57. In an embodiment, prongs 56 alsoinclude distal slots 53 and lateral openings 59.

Referring to FIGS. 8-11, in an embodiment, a support member 60 isattached to the distal portion of the pronged attachment tip 52. Thesupport member has pins 62 designed to ride in the distal slots 53. Acentral recess 64 is disposed within the support member 60 and sized andshaped to receive the support shaft 58. In one embodiment, the supportshaft 58 has threads and the central recess 64 may be tapped tocorrespond to the threads formed on the support shaft 58.

Referring to FIGS. 1 and 8-11, in one embodiment, guide member or fin 66projects in a generally orthogonal outward direction from the prongedattachment tip 52. Fin 66 is sized, shaped and configured to slidewithin tracking slot 38 of guide member 18 to help guide the prongedattachment tip 52 and the implant 6 into a proper position between thevertebrae.

In one embodiment, the fin 66 may be monolithically formed as part ofthe pronged attachment tip 52. In other embodiments, the fin 66 is aseparate piece that can be secured to the pronged attachment tip 52 in anumber of ways including but not limited to using a rib and recess, railand groove, a fastener or adhesive. In an example embodiment, the fin 66is triangular shaped in cross section or tapered. However, the fin 66may have any size or shape suitable to cooperate with the tracking slot38.

Referring to FIGS. 8-11, the pronged attachment tip 52 is adapted togrip an implant 6 and act as a retainer in a manner that is secure butcan also easily be released when necessary. Referring to FIG. 9, implant6 may include recesses 7 adapted to cooperate with ribs 57 to provide aninterference fit between the pronged attachment tip 52 and implant 6.Prongs 56 are pivotable about base portion 54 to accommodate implants 6of differing width, size and shape.

Referring to FIGS. 1, 3, 4, and 8, the attachment tip 40 and prongedattachment tip 52 are designed to be attached in multiple configurationsrelative to the general plane of operation of the inserter instrument12. Referring to FIGS. 1 and 3, in an example embodiment, attachment tip40 is oriented such that fin 50 projects upwardly (as shown) relative tothe plane of the inserter instrument 12.

Referring to FIGS. 1 and 8, the pronged attachment tip 52 is orientedsuch that the fin 66 projects downwardly (as shown) relative to theplane of the inserter instrument 12. In another embodiment, theattachment tip 40 could be attached and configured so that the fin 50projects orthogonally downwardly or upwardly, and the pronged attachmenttip 52 could be configured so that the fin 66 projects orthogonallyupwardly. In all of the foregoing configurations the fin would stillslide along the tracking slots 38 to guide and ensure proper alignmentof the attachment tip 40, 52. In an embodiment, the attachment tips maybe made of steel composite/ However, any material suitable for surgicalapplications may be used, such as but not limited to plastic, compositeand metal.

Referring to FIGS. 1 and 11, in an example operation, implant inserter10 is used during a surgical procedure to deliver an implant 6 to a discspace (not shown) formed between vertebrae. The inserter 12 is first setto a start position where the central shaft 16 is fully withdrawn andthe tip of the central shaft 16 is proximate the distal end of the body.Next, a single distractor arm 38 or the pair of distractor arms 38 canbe pivoted open to provide space to insert an attachment tip 40,52. Forpurposes of this example operation, the pronged attachment tip 52 isjoined to the tip adapter 20 and central shaft 16.

The implant 6 can then be inserted into the pronged attachment tip 52 sothat it is firmly gripped by the pronged attachment tip 52. Distractorarms 18 are pivoted to a closed position as shown in FIG. 1, such thatthe fin is aligned with and projects through either the upper or lowertracking slot 38 to ensure proper alignment and tracking Next, theimplant inserter 10 is placed so that the stop members 39 abut theoutside of the vertebrae and the distal ends of the distractor arms 38enter the disc space. Stop members 39 provide a stable support for theimplant inserter 10 so that it does not become inadvertently dislodgedduring operation.

The central shaft 16 is driven forward by pushing or rotating the handle11 depending on the mode of the actuator 23. As the central shaft 16moves forward, the pronged attachment tip 52 and implant 6 move along ina distal direction towards the disc space. Also as the central shaft 16moves forward, the distractor arms 38 move away from each other toeffectively spread the disc space.

In an example embodiment, during the insertion process, the prongedattachment tip 52 and implant 6 are moved beyond the distal ends of thedistractor arms 38. During the final insertion of the implant 6 into thedisc space, the fin 66 can abut against the vertebrae. The tapereddesign of the fin tracks the profile of the vertebrae and providesadditional support during final insertion of the implant 6 into the discspace, and for the start of withdrawal. After the implant 6 has beensituated per requirements, the central shaft 16 may be pulled out of thesurgical site by pulling freely, twisting the handle 11 or using thedial 13. This will move the central shaft 16 from a distal to proximaldirection out of the space between the vertebrae.

In example embodiments, the implant inserter 10 can be used forposterior, lateral, oblique, anterior and other alternate approaches.

In the foregoing description and in the accompanying drawings, specificterminology and drawing symbols have been set forth to provide athorough understanding of the disclosed embodiments. In some instances,the terminology and symbols may imply specific details that are notrequired to practice those embodiments.

Various modifications and changes may be made to the embodimentspresented herein without departing from the broader spirit and scope ofthe disclosure. For example, features or aspects of any of theembodiments may be applied, at least where practicable, in combinationwith any other of the embodiments or in place of counterpart features oraspects thereof. Accordingly, the specification and drawings are to beregarded in an illustrative rather than a restrictive sense.

The invention claimed is:
 1. An instrument for inserting an implantbetween vertebrae, comprising: a body having a through bore; a tubularportion received in the body, wherein the tubular portion comprises atleast one window; a central shaft movable within the through bore, thecentral shaft having a proximal end and a distal end; a pair ofdistractor arms having proximal portions and distal portions, theproximal portions pivotally coupled to the body and distal portions forengagement between the vertebrae; tracking slots formed in and extendingthrough surfaces of and along longitudinal axes of the distractor arms;an attachment tip operably connected to the central shaft, theattachment tip configured to grip the implant; and a single guide memberprojecting outward from the attachment tip, wherein the attachment tipis removably connectable to the central shaft in multipleconfigurations.
 2. The instrument of claim 1, wherein the distal end ofthe central shaft has a tip adapter extending therefrom.
 3. Theinstrument of claim 2, wherein the attachment tip is connectable to thetip adapter.
 4. The instrument of claim 3, wherein the attachment tipincludes a bore configured to receive the tip adapter.
 5. The instrumentof claim 4, wherein a hinge pivotally connects the prong to theattachment tip.
 6. The instrument of claim 1, wherein the attachment tipincludes a prong extending from a forward surface.
 7. The instrument ofclaim 1, further comprising a switch to actuate the central shaftbetween a rotational mode and a longitudinal mode.
 8. The instrument ofclaim 1, wherein the attachment tip includes a retainer configured tohold and release the implant.
 9. An instrument for inserting an implantbetween vertebrae, comprising: a body having a through bore; a tubularportion received in the body, wherein the tubular portion comprises atleast one window a central shaft movable within the through bore, thecentral shaft having a proximal end and a distal end having a tipadapter; a handle portion attached to the proximal end of the centralshaft; a pair of distractor arms having proximal portions and distalportions, the proximal portions pivotally coupled to the body and distalportions for engagement between the vertebrae; a plurality of trackingslots extending through surfaces of and along a longitudinal axes of thedistractor arms; an attachment tip operably connected to the tipadapter, the attachment tip configured to releasably grip the implant;and a single fin projecting outward from the attachment tip, wherein theattachment tip is removably connectable to the tip adapter in multipleconfigurations.
 10. The instrument of claim 9 wherein the attachment tipincludes a bore configured to receive the tip adapter.
 11. Theinstrument of claim 9 wherein the attachment tip includes a prongextending from a forward surface.
 12. The instrument of claim 11 whereina hinge pivotally connects the prong to the attachment tip.
 13. Theinstrument of claim 9 wherein the attachment tip includes a retainerconfigured to hold and release the implant.
 14. The instrument of claim9 wherein the body includes a drive action button selectively engageableto switch forward motion of the central shaft between a rotational modeand a longitudinal mode.
 15. The instrument of claim 9 wherein thecentral shaft includes a threaded portion and an unthreaded portion. 16.The instrument of claim 9 wherein the distal end of the distractor armshave stop members.
 17. An instrument for inserting an implant into anintervertebral space comprising: a body having a through bore; a tubularportion received in the body, wherein the tubular portion comprises atleast one window; a central shaft slidably and rotatably movable withinthe through bore, the central shaft having a proximal end and a distalend; a handle portion transversely attached to the proximal end of thecentral shaft; a first distractor arm having a proximal portion and adistal portion, proximal portion of first distractor arm pivotallycoupled to the body and distal portion of first distractor armextendable into the intervertebral space; a second distractor arm havinga proximal portion and a distal portion, the proximal portion of seconddistractor arm pivotally coupled to the body and the distal portion ofsecond distractor arm extendable into the intervertebral space; an uppertracking slot formed in and extending through a surface of and along alongitudinal axis of the first distractor arm and a lower tracking slotformed in and extending through the surface of and along a longitudinalaxis of the second distractor arm; a tip adapter formed at the distalend of the central shaft; an attachment tip operably connected to thetip adapter, the attachment tip configured to grip the implant; and asingle fin monolithically formed on and projecting outward from theattachment tip, wherein the attachment tip is adapted to engage the tipadapter in multiple configurations so that the single fin extendsthrough either the upper tracking slot or the lower tracking slot. 18.The instrument of claim 17, wherein the attachment tip has a boreconfigured to receive the tip adapter.
 19. The instrument of claim 17,wherein the attachment tip has a pair of substantially parallel prongelements pivotally connected thereto.
 20. The instrument of claim 17,wherein the body includes a drive action button selectively engageableto switch forward motion of the central shaft between a rotational modeand a longitudinal mode.